Problem with junction of folders ?

Black Winny · Post by **Black Winny** » Tue Sep 08, 2009 12:10 am

It seems that DV Duplicate Cleaner has a unattended behavior with files that are elements of folders associated by a NTFS Junction... and above all when these folders are subfolders of the junction ! A curious bevahior at the step of detection... having for consequence to lead to a complete destruction if one chooses to destroy or hardlink the related files.

So this curious behavior in the detection could be destructive in the management of files by the user, perhaps...

To be confirmed... if there are volunteers.

Anyway... DV Duplicate Cleaner is yet really the best software in dup detectors and cleaners ! To be encouraged !

Black Winny

DV · Post by DV » Tue Sep 08, 2009 1:58 pm

Hi, Glad you like Duplicate Cleaner.
Can you explain the above problem a bit more? Are you saying that deleting or hardlinking a file in NTFS junction folder deletes the whole folder?

DellDude · Post by **DellDude** » Fri Jun 18, 2010 4:36 am

The problem with junctions in Windows is that a junction is basically a hardlinked folder. If a junctioned folder is deleted, since there is really just one folder with multiple references, all junctions have lost there target and all of the data is lost. When deleting a junctioned folder, the JUNCTION should be deleted, NOT the one and only copy of the data. See an excellent explanation in http://schinagl.priv.at/nt/hardlinkshel ... #junctions - FYI Link Shell Extention is an excellent hardlink tool that gets around this problem with its hardlink clone feature that substitutes a folder filled with hardlinked files for a junction without the danger inherent in junctions.

Colombo · Post by **Colombo** » Mon Aug 09, 2010 1:20 am

The issue about junction points is very important. Look how big was the damage for me. I bought a new hard disk and installed Windows Vista there. With the two hard disks attached to the same PC, I used Duplicate Cleaner to remove duplicates from the old hard disk, which contained junction points to C:\ (the new hard disk). Hence, Duplicate Cleaner detected files that only existed in C: as duplicates. When such files were deleted only from the old hard disk, the files were fully wiped out from the C:, rendering my new system corrupt.

Duplicate Cleaner is a great tool, but ignoring junction points is particulary dangerous to most users.

DV · Post by DV » Mon Aug 09, 2010 3:01 pm

Sorry about your lost files, Colombo. Thanks all for the Junction Points information - very useful.
I have put together code now which detects junction point folders, and will work this into Duplicate Cleaner 2.0. Not sure where to add it yet - maybe an option excluding any folders of this type from the scan.